In the United States, an estimated 3.2 million persons are living with hepatitis C virus (HCV) infection. HCV transmission occurs primarily through percutaneous exposure to blood, and persons who inject drugs are at greatest risk for infection. The role of sexual transmission of HCV has not been well defined. However, reports over the past decade, mainly from Europe, have implicated sexual transmission of HCV among human immunodeficiency virus (HIV)–infected men who have sex with men (MSM).